Method of impregnating paper receptacles



Oct. l2 1926.

. l1922i 2 Sheets-Sl'leet 1 l Original Filed Dac. 3l

INVENTEOR'. J wfg-* oct. 12, 192e. 1,602,835v

J. D. REusNYDERl METHOD OF yIMPREGNATING PAPER RECEPTACLES original Filed Dec. 31, 1921 2 Sheets-Shea".I 2

7/277//6 Awa IMJ/W6 (20/J ,4Z/ ATTORNEYS.

Patented Oct. 12,1926.

v1,602,835 PATENT ortica.

JAMES D. REIFSNYDER, OF BROOKLYN, NEW YOIBK, ASSIGNOB, BY MESNE Asl-SIGN'- MENTS, TO, TULIP CUP CORPORATION, OF NEW YORK, N'. Y., A CORPORATION OF' DELAWARE.

METHOD OF IMPREGNATING- PAPER EECEPTAOLES.

original application iiled December 31, 1921, Serial No. 526,259. Dividedandthis application iiled J'anuary 1:1,"1924- Serial No. 686,223.

The invention relates to an improved method of impregnating paper receptacles. It is especially useful foi' the, impregnation of individual paper drinking cups but may 5 also be used for the impregnation of other paper receptacles. This application is a division of my application improvements in impregnated individualpaper drinking cup, Serial No. 526.259, filed December 31, 1921.

. One of the objects of the invention is the provision of a simple and effective method of impregnating or treating individual paper cups, or other paper receptacles? Another object of the invention is the provision receptacle with a water proofing material whichis 'not injurious andwill not give an appreciable odor or taste when put to the lips. and which will not have an appreciable coating of the indurating material, particularly on its outer surface. Another object is the provision of a method for so treating a cup or other receptacle as 'to render it especially usefulfor holding hot liquids.

The invention consists inthe method of impregnating or treating paper .receptacles hereinafter described according to the preferred'manner of practicing the same and the invention will be more particularly pointed out in the appended claims.

It has heretofore been the practice to make individual paper drinking cups both with plain and pleated walls, land to coat such cups by dipping them in melted paraffin, but cups thus made have a distinct coat- 'ing of paraffin on the inner and outer.l surfaces, including the rim. This parailin coating is unpleasant both to the'touch of the lips and fingers, and is made more so,

40 when any warm drink is poured into the cup. It may also 'produce spots on gloves. Furthermore, individual paper Cupsheretofore made' are not suitable for holding hot liquids, since such cups will not hold ,their 45 forms and remain tight with fluids of a temperature of over about 120 Fvah.v Notwithstanding the decided coating of paraflin, these known cups are not useful for hot drinks which should be dispensed or poured at a'temperature ofnot much below 150l of a method for impregnating a cup or other* vwith the accompanying drawings'illustrating the preferred form 'of cup.

Referring to thedrawings, Fig. 1 is a perspective View of a pleated cup impregnated by vthe method' embodying my invention;

Fig. 2 is a sectional view of the same taken on line 2-2;

- Fig. 3 is an` enlarged section at the rim taken on line 8-3 of Fig. 2. Flgs. 4, and 6 are diagrammatic views 70 indicating steps of the process.- l The cup 1 shown in the drawings is a pleatedcu'p shown and fully described in the United States Letters Patent No. 1,310,698, and is'made of a'suitable single 75' blank of material so as to provide pleated side walls 2 and a rolled rim l3. Cups of this character have three thicknesses of paper at certain portions thereof as shown in Fig. 3, where the pleats or folds occur. l

While the invention is equally applicable to plain smooth surfaced cups, it is especially advantageous in impregnating pleated cups, because due to, the folds and irregular surfaces, when such cups aref dipped in paraiin in the usiia'l way, i. e., in paraffin havlng a melting point'ofabout 125 F., and at a temperature of about 175 F., they become coated with a very excessive amount of paraffin. .90

In impregnating the cup according to my preferred process, I use a waxy impregnating material having a relatively high melting point and consisting preferablyof -a mixture of a vegetable wax. withV a high 95 melting point, such as carnauba having a meltlng point of about 180 vFall. and ahigh grade paraiiin, -i. e.,- one having a .melting point of about Fah. I preferably use y about 20% by weight of the wax and 80% 100 of paralin. This waxy-mixture has a rela tively high melting point of. about t0 f Fah.-

I heat this mixture up tothe relatively high temperature of about 250 Fah., then 105 apply it in liquid form to the cup, preferably only to a portion of the,cup, so as not to get an excessive amount of the mixture on the cup, and then whil'e the coating of the mixture on portions of the cup is yet hot, I subject the cup to'heat .so as to cause the impregnating liquid to spread. over the whole surface of the cup and impregnate the same. I preferably applytlie impregnating liquid to the inside of the cup by pouring it into the cup, sufcient to fill the cup fromone-eighth y to one-quarter full, then immediately empty the liquid from the cup while giving the cup a twist of from one-half to a full revolution. This causes the liquid to flow over the inner surface in a spiral-like path from the bottom toward `the prim, so as to leavey the liquid distributed over only -portions of the cup extending from the bottom to the rim.y ,'Ihe cup is then passed into an oven kept at a temperature of about 180 to 200 Fah., as a lower limit, to which temperature the cup .is subjected for about 45 seconds to a minute.

The temperature of the 'oven should, of course, be kept below that at which discoloring or charring of the cup takes place, this temperature varying withthe length of the oven and the time required for the cu s to pass through the same. This keeps the liquid thin so that it will readily spread over theentire surface and thoroughly impregnate the shell of the cup.

In this manner I can produce a cup having substantially no coating on the outside, and

' little or none on the inside, and yet having 'on cups simply dippedy in hot parailin. But

by applying the liquid on only portions of the cup and keeping theliquid hot, 'the uncoated part of the paper cup shell will absorb and take up substantially all of the liquid on the coated portions of the cup so that the liquid will spread all over and thorougly' impregnate the shell to such an extent as to leave substantially no excess of the im- .,pregnating solution on the surface of the cup. I have found that when this process is properly carried out and where a proper waxy material with a relatively high melting point such as that. described,'is used, the cup is so thoroughly impregnated that it will` hold liquids at a temperature of about 170 Fah. and yet the surface of the cup is substantially free of any surface coating so that the cup isdry and clean to the touch rather than having an oily waxy feel; and the outer surface, even when scraped with a? shcarp edge, shows no coatinv. 'Ilie cup is of a pleasing white uniform color, slightly translucent, and is, by the iinpregnation, rendered stier and firmer than it would otherwise be, and this without having the pleats gummed together by the impregnating material, as has been the pracaxis during the tilting, the liquid in the cup moving in separated spiral paths over the inner surface of the cup during this motion `as is indicated 'by the dotted lines 5. In

Figure 6 the cup is shown as placedwithin an'oven 6 whereby heat is supplied to keep the impregnating material on the inner surface of the cup liquid, to allow the same to spead to cover the entire inner surface and to be absorbed within the body of the cup.

" While I have described the preferred titi method of impregnating a cup or other paper receptacle, it will be understood by those p skilled in the art, after understanding my invention, that modifications.v may be made therein without departing from the spirit or scope of the invention, and I aim in the appended claims to cover all such moditications as come within the spirit or scope oit the invention.

It is noted that suitable apparatus by which the method herein described and claimed may effectively be practiced is described and claimed in my co-pending application Serial No. 532,181, filed January 27, 1922, entitled Apparatus for treating paper cups and the like.

What I claim is:

1. The method of impregnating thin individual paper cups which comprises, applying a hot impregnating liquid to separated portions only of the cup surface, and subl ,jecting the cup to an atmosphere suciently hot to keep the impregnatin material on the cup in a liquid conditionan permitting the same to spread over the surface and impregnate the cup. y.

2. The method of impregnating individual paper cups which comprises, applying a hot impregnating liquid of relatively high melting point, at a temperature ofl not lessthan about 200 F., to separated portions only ot the cup surface, and subjecting the cup to an atmosphere sufficiently hot to keep the impregnating materialen the cup a liquid a hot impregnating liquid to the insi condition and permitting the same to spread over the surface and impregnate'the cup.

3. Method of impregnating thin paper receptacles which comprises pouring a hotimpregnating liquid into the receptacle to only partly fill it, and then emptying the material from the receptacle while giving the receptacle a twisting motion so as to coat a spirallike portion of the receptac1e,`and then passing the receptacle into an oven to maintain the impregnating iuid hot to effect spread- 'ing of the liquid over the shell of the receptacle and impregnation of the shell.

4. The method of impregnating thin paper receptacles which comprises, aplplying e only of the receptacle, quickly inverting the receptacle to pour out the surplus, and then su jecting the receptacle to heatwhile the impregnating material on the. inner surface thereof is still hot.

5. The method of impregnating thin paper cups whicheomprisesLpouring a measured relatively small quantity of hot impregnating liquid into the cup, tilting the cup to empty it and at the same time giving it a diierent motion so that the liquid therein will flow laterally relatively to the cup.

In testimony whereof I have signed my name to this specification.

JAMES D. REIFSNYDER. 

